Switched capacitor DC-DC power converters are known in the art and have previously been utilized in various types of head-wearable hearing devices such as hearing aids and hearing instruments. Switched capacitor DC-DC power converters are often utilized to convert a DC input voltage delivered by an energy or power source, such as a rechargeable battery, of the hearing device into a higher or lower DC output voltage suitable for various types of active components of the device. Switched capacitor DC-DC power converters possess certain attractive properties compared to their inductor-based counterparts—for example a relatively low level of electromagnetic emission due to the lack of stored energy in magnetic fields of inductors. Dimensions of switched capacitor DC-DC power converters may be compact and their energy conversion efficiency relatively high. Different topologies of switched capacitor DC-DC power converters are capable of providing DC voltage step-up (i.e. boost) and DC voltage step-down (i.e. buck) with a topology dependent optimum voltage conversion ratio for example 1:2 or 1:3 step-up conversion and 2:1 and 3:1 step-down conversion.
The head-wearable hearing devices may additionally comprises a magnetic inductance antenna for receipt and/or transmission of magnetically coupled wireless data signals through a wireless communication channel or link. The wireless communication channel may form part of an ear-to-ear communication system of a binaural hearing aid system allowing data signals and digital audio signals to be exchanged between the head-wearable hearing device and another head-wearable hearing device mounted at, or in, the user's opposite ear. Co-existence of the magnetic inductance antenna and the switched capacitor DC-DC converter often represents a significant challenge because of the very compact dimension of a housing of the head-wearable hearing device. The compact housing dimensions limit the maximum physical distance between the magnetic inductance antenna and the DC-DC power converter and its associated wiring and external components. Hence, pulsed electromagnetic noise bursts caused by charging current pulses running in the flying capacitor(s) and output capacitor(s) of the switched capacitor DC-DC converter are rather effectively coupled into the magnetic inductance antenna as interfering noise pulses that deteriorate reception of the desired wireless digital data signals.
Hence, there remains a need in the art for improvements of switched capacitor DC-DC converters to achieve reductions of electromagnetic noise disturbances of magnetic inductance antennas of head-wearable hearing devices like hearing aids and headsets.